Request received; client may continue.

Server switching protocols as requested.

Request accepted; processing not complete (WebDAV).

Hints for preloading resources while preparing response.

Request succeeded.

Resource created successfully.

Request accepted for processing but not completed.

Success with empty response body.

Partial resource returned (range requests).

Resource permanently moved to a new URI.

Temporary redirect to another URI.

Response available at another URI via GET.

Cached version is still valid.

Temporary redirect; method must not change.

Permanent redirect; method must not change.

Malformed request syntax or invalid framing.

Authentication required or failed.

Server understood but refuses to authorize.

Target resource does not exist.

HTTP method not supported for this resource.

Server timed out waiting for the request.

Request conflicts with current resource state.

Resource permanently removed.

Request body larger than server allows.

Payload format not supported.

Well-formed but semantic errors (validation).

Rate limit exceeded.

Unexpected server condition.

Server does not support the requested functionality.

Invalid response from upstream server.

Server temporarily overloaded or down.

Upstream server failed to respond in time.